Philips says it tried to make the Fidelio L1 headphones as accurate and neutral as possible, closer to something like the AKG Q701 than their obvious high street rivals, like the House of Marley Destiny TTR and Monster Beats by Dr. Dre Studio.
First, let's cover the good. These headphones offer great clarity and better bass management than we expect to see in a set we're not embarrassed to wear out of the house. The top-end isn't ultra-smooth and laid-back like the top at-home Sennheiser HD 650 headphones, but it is accurate and well-rendered as promised, boasting an uncoloured take on the source material.
There was something nagging away at our ears that took a while to identify, though. The Fidelio L1 tick a lot of boxes instantly - voluminous but not too heavy bass, good top-end and a seemingly versatile signature - but after a while we couldn't get over the sense that there's something slightly unsatisfying about it.
Then we realised that there's a cloying sense to the low-mid range that robs the bottom end of its impact and detracts from the other-wise impressive transparency of the upper registers. It could be identified as warmth, but it doesn't feel like a positive aspect in-situ. Thankfully, there is a solution.
We noticed an improvement in mid-range openness when the Fidelio L1 were used with a headphone amplifier. Even the ultra-portable, low-cost Fiio E6 miniature headphone amp had a positive effect, letting the bottom-end reclaim its lost impact. The bass is there - quite a lot of it, in fact - it just gets the limelight stolen from it by the upper bass and low-mids.
In an at-home headphone, needing a headphone amp for best results isn't too much of an issue at this enthusiast level, but it may put off those who just prefer to sling the things on and go - especially as the 26Ohm impedance suggests they'll be happy to work off a player's output alone. In our opinion, the sonic benefits are worth the extra effort of an amp, though. With that bit of extra power, they offer an extremely enjoyable listen - rich, detailed and lots of fun for a set that's self-consciously serious. It's also possible that these 'phones will bed in a bit more after extended listening, as we found with the Phiaton PS 500.
The Philips Fidelio L1 have the design chops to work as a dual-purpose for many - as a music/gaming/TV headset while you're on the sofa, and as entertainment on the way to work. No, they won't block out as much sound as the Bose QuietComfort 15 or the Beats Solo HD, but they will stop people around you from hearing your tunes. And that's the main thing, in our (terribly socially conscious) book.
If you're out for a set of headphones to use exclusively at home - and don't live with noisy children of housemates, though, you can get an airier and more open sound from an all-out open set of headphones. The Fidelio L1 do benefit from their semi-open design sonically, but the sound stage is only wide for a closed set - not an open one.
The Philips Fidelio L1 are semi-open headphones that want to stay at your side whether you're at home or out around town. For the most part, they do the job perfectly. They are extremely well-made, look pretty natty and are comfortable as long as it's not steaming hot outside. Their sound is clear at the top-end, but benefits from amplification to relax the otherwise bundled-up low-mid range.